Both good points GG and MEL. Yes of course you can't vote for yourself doh!

Keep in mind I didn't write the code that requires the comment. I may be able to mod it so it doesn't require the text.

As far as the thumbs down, we had it before and from an administration standpoint it is very useful. When I see someone who is getting negative karma (which I see as an admin), then I know when someone is being out of line or spamming people. I've used the negative karma clues to track down spammers and ban their accounts. Obviously the concept is more of an ebay type rating than the standard karma.

I do think the text should be optional and it should "appear" somewhere if it is used, like ebay's feedback. I can see that the text is stored in the database in a strange place so maybe that is more of an administrative thing.